1. Field of the Invention
The present invention relates to valves and, in particular, to valves of a type wherein a movable valve member is coupled to an actuating linkage by means of a cross pin retained in a socket in the valve member to accommodate pivotal movements of the linkage relative to the valve member during opening and closing of the valve.
2. Description of the Prior Art
A common type of valve is a bottom outlet valve of the type manufactured by Midland Manufacturing Corporation. Such valves include a housing defining an annular valve seat against which a poppet valve member is reciprocatively movable by means of an actuating linkage. The linkage includes a cam lever which has an upper end thereof received in a socket in the bottom of the valve member and having a bore diametrically therethrough receiving a cross pin, the ends of the pin being accommodated in a counterbore of the socket. The pin is retained in place by a retaining plate which is fixed to the valve member and engages the end portions of the pin to clamp it in the counterbore. The pin accommodates slight pivotal movements of the cam arm relative to the valve member during opening and closing of the valve. During such valve operation, significant forces are exerted on the pin in directions generally perpendicular to its axis. When the load on the valve member is sufficiently high, these forces may be sufficient to bend the pin, thereby interfering with free pivotal movement of the cam lever and impairing operation of the valve.